A mobile communication system has been developed to provide an audio service to a user while securing mobility of the user. Yet, the mobile communication system is gradually expanding its service area not only the audio service but also a data service and has developed to the extent as much as providing fast data service nowadays. Yet, since the currently providing mobile communication system is experiencing a lack of resources and users are requiring a faster service, a more advanced mobile communication system is required.
One of most important things of a next generation wireless access system is to satisfy data transfer rate demand. To this end, ongoing effort to develop various technologies including MIMO (multiple input multiple output), CoMP (cooperative multiple point transmission), a relay and the like is in progress.
In addition, application of a heterogeneous network consisting of a macro-pico or a macro-femto is expanding to accept rapidly increasing wireless data demand. In this case, a pico cell or a femto cell is positioned within a macro cell. In this circumstance, a user equipment positioned at a cell boundary of duplicated cells may receive signals from each of the cells and the signals act like interference with each other.